gene

The definitions used in this glossary of terminology either have been
provided by the authors of the articles, or have been extracted wholly or in
part, or paraphrased from the following sources: The American Medical
Association Encyclopedia of Medicine, Charles B. Clayman, MD, Medical
Editor, Random House, New York, 1989; Biotechnology from A to Z, 2d
Edition, William Bains, Oxford University Press, New York, New York, 2002;
A Dictionary of Genetics, 6th Edition, Robert C. King and William D.
Stansfield, Oxford University Press, New York, New York, 2002; Dorland's
Illustrated Medical Dictionary, 29th and 30th Editions, W. B. Saunders
Company, Philadelphia, 2000, 2003; Genes VII, Benjamin Lewin, Oxford
University Press, New York, New York, 2000; The Gale Encyclopedia of
Genetic Disorders, Volumes I and II, Stacey L. Blachford, Ed., Thomson
Learning, New York, New York, 2002; The Merriam-Webster Dictionary,
Merriam-Webster, Inc., Springfield, Massachusetts, 1997; Molecular
Biology of the Cell, 3rd Edition, Bruce Alberts, et al., Garland
Publishing, 1994; The Random House Dictionary of the English
Language, Unabridged Edition, 1966; Webster's Ninth New Collegiate
Dictionary, 1991.

DNA molecule

DEFINITION:

synthesis

DEFINITION:

The artificial building up of a chemical compound, by the union of its elements or from other suitable starting materials.

polypeptide chain

DEFINITION:

The structural element of protein, consisting of a series of amino acid residues (peptides) joined together by peptide bonds.

RNA molecule

DEFINITION:

Ribonucleic acid molecule.

coding

DEFINITION:

See genetic coding.

coding

DEFINITION:

See genetic coding.

heredity

DEFINITION:

1. The genetic transmission of a particular quality or trait from parent to offspring. 2. The genetic constitution of an individual.

transmitted

DEFINITION:

1. Passed or transferred, as of a disease from one individual to another, or of neural impulses from one neuron to another.

2. Referring to heritable qualities communicated from parent to offspring.

progeny

DEFINITION:

Offspring, or descendants.

locus

DEFINITION:

1. A general anatomical term for a site in the body. 2. In genetics, the position of a gene on a chromosome, different forms of genes (alleles) being found at the same position on homologous chromosomes.

genes

DEFINITION:

In the singular: A segment of a DNA molecule that contains all the information required for synthesis of a product (polypeptide chain or RNA molecule), including both coding and non-coding sequences. It is the biological unit of heredity, self-reproducing, and transmitted from parent to progeny. Each gene has a specific position (locus) on the chromosome map. From the standpoint of function, genes are conceived of as structural, operator, and regulatory genes.

wild-type gene - The normal allele of a gene, sometimes symbolized by +.

X-linked gene - A gene carried on the X chromosome; the corresponding trait, whether dominant or recessive, is always expressed in males, who have only one X chromosome. X linkage is used sometimes synonymously with sex linkage since no genetic disorders have as yet been associated with genes on the Y chromosome.

operator

DEFINITION:

1. One who performs an operation, or operates a mechanical device. 2. Operator gene .

regulatory

DEFINITION:

Exerting a controlling influence.

genes

DEFINITION:

In the singular: A segment of a DNA molecule that contains all the information required for synthesis of a product (polypeptide chain or RNA molecule), including both coding and non-coding sequences. It is the biological unit of heredity, self-reproducing, and transmitted from parent to progeny. Each gene has a specific position (locus) on the chromosome map. From the standpoint of function, genes are conceived of as structural, operator, and regulatory genes.

wild-type gene - The normal allele of a gene, sometimes symbolized by +.

X-linked gene - A gene carried on the X chromosome; the corresponding trait, whether dominant or recessive, is always expressed in males, who have only one X chromosome. X linkage is used sometimes synonymously with sex linkage since no genetic disorders have as yet been associated with genes on the Y chromosome.

wild-type

DEFINITION:

In genetics, the standard phenotype for any experimental organism; also a gene that determines a standard phenotypic trait. See also under gene .

allele

DEFINITION:

Any alternative form of a gene that can occupy a particular chromosomal lucus. In humans and other diploid organisms there are two alleles, one on each chromosome of a homologous pair.

X-linked gene

DEFINITION:

A gene carried on the X chromosome; the corresponding trait, whether dominant or recessive, is always expressed in males, who have only one X chromosome. X linkage is used sometimes synonymously with sex linkage since no genetic disorders have as yet been associated with genes on the Y chromosome.

X chromosome

DEFINITION:

The female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in man and other male-heterogametic species.

corresponding

DEFINITION:

Agreeing or conforming.

trait

DEFINITION:

1. Any genetically determined characteristic.

2. Commonly used in medicine to designate the condition prevailing in the heterozygous state of a recessive disorder, as in sickle cell anemia.

3. A distinctive behavior pattern.

dominant

DEFINITION:

1. Exerting a ruling or controlling influence.

2. In genetics, capable of expression when carried by only one of a pair of homologous chromosomes.

3. A dominant allele or trait.

recessive

DEFINITION:

1. Tending to recede; not exerting a ruling or controlling influence; in genetics, incapable of expression unless the responsible allele is carried by both members of a pair of homologous chromosomes. 2. A recessive allele or trait.

expressed

DEFINITION:

1. Showing a detectable effect of a gene.

2. Made known; shown.

3. Squeezed out; extracted by pressing.

X chromosome

DEFINITION:

The female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in man and other male-heterogametic species.

X linkage

DEFINITION:

In genetics, the association of genes having loci on the same chromosome (the X chromosome).

sex linkage

DEFINITION:

In genetics, the association of genes having loci on the same chromosome (the X chromosome).

genetic

DEFINITION:

1. Relating to or determined by the origin, development, or causal antecedents of something.

2. Of, relating to, or being a gene.

disorders

DEFINITION:

Derangements or abnormalities of function; morbid physical or mental states.

genes

DEFINITION:

In the singular: A segment of a DNA molecule that contains all the information required for synthesis of a product (polypeptide chain or RNA molecule), including both coding and non-coding sequences. It is the biological unit of heredity, self-reproducing, and transmitted from parent to progeny. Each gene has a specific position (locus) on the chromosome map. From the standpoint of function, genes are conceived of as structural, operator, and regulatory genes.

wild-type gene - The normal allele of a gene, sometimes symbolized by +.

X-linked gene - A gene carried on the X chromosome; the corresponding trait, whether dominant or recessive, is always expressed in males, who have only one X chromosome. X linkage is used sometimes synonymously with sex linkage since no genetic disorders have as yet been associated with genes on the Y chromosome.

Y chromosome

DEFINITION:

The male sex chromosome, being the differential sex chromosome carried by half the male gametes and none of the female gametes in man and in some other male-heterogametic species in which the homologue of the X chromosome has been retained.